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This content will become publicly available on September 1, 2024

Title: N-induced soil acidification triggers metal stimulation of soil methane oxidation in a temperate steppe ecosystem
Award ID(s):
2145130
NSF-PAR ID:
10446751
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Soil Biology and Biochemistry
Volume:
184
Issue:
C
ISSN:
0038-0717
Page Range / eLocation ID:
109098
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  1. Abstract

    Long‐term soil warming can decrease soil organic matter (SOM), resulting in self‐reinforcing feedback to the global climate system. We investigated additional consequences of SOM reduction for soil water holding capacity (WHC) and soil thermal and hydrological buffering. At a long‐term soil warming experiment in a temperate forest in the northeastern United States, we suspended the warming treatment for 104 days during the summer of 2017. The formerly heated plot remained warmer (+0.39 °C) and drier (−0.024 cm3H2O cm−3soil) than the control plot throughout the suspension. We measured decreased SOM content (−0.184 g SOM g−1for O horizon soil, −0.010 g SOM g−1for A horizon soil) and WHC (−0.82 g H2O g−1for O horizon soil, −0.18 g H2O g−1for A horizon soil) in the formerly heated plot relative to the control plot. Reduced SOM content accounted for 62% of the WHC reduction in the O horizon and 22% in the A horizon. We investigated differences in SOM composition as a possible explanation for the remaining reductions with Fourier transform infrared (FTIR) spectra. We found FTIR spectra that correlated more strongly with WHC than SOM, but those particular spectra did not differ between the heated and control plots, suggesting that SOM composition affects WHC but does not explain treatment differences in this study. We conclude that SOM reductions due to soil warming can reduce WHC and hydrological and thermal buffering, further warming soil and decreasing SOM. This feedback may operate in parallel, and perhaps synergistically, with carbon cycle feedbacks to climate change.

     
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